1. Field of the Invention
This invention is in the field of hand trucks for moving unwieldy and heavy objects in which the object to be moved is positioned between a pair of such hand trucks. Each hand truck is provided with one pair of fixed wheels and a pair of castered wheels. By adjusting the heights of the load relative to the hand trucks, the weight of the load is carried by the fixed wheels of one truck and the castered wheels of the other which facilitates one person maneuvering the loaded trucks.
2. Description of the Prior Art
In buildings, both domestic and commercial, there is frequently a need to move unwieldy objects, unwieldy for one or two men because of either size, or weight, or both of the object. Examples are refrigerators, stoves, vending machines, safes, rolled rugs, coils of wire, coils of cable and the like; particularly those that weigh substantially in a range of from 500 to 1000 pounds. Such objects are frequently moved without the use of powered equipment, by hand trucks, for example, and it is known to support objects of the foregoing types between a pair of hand trucks.
One problem with using a pair of prior art hand trucks to move such objects arises because the wheels of each hand truck are swivelled, or castered, with the result that to maneuver a large heavy and unwieldy load requires at least two persons, one at each truck to steer, or maneuver, the combination because of the tendency of such easily turned caster wheels to follow changes in contour, or resistance, of the surface over which the trucks are moving.
Another type of prior art hand truck has a single roller which extends substantially the full width of the hand truck. Such an arrangement makes turning the loaded hand trucks difficult, if not almost impossible, which is also the case if the hand trucks are provided with fixed wheels instead of castered wheels.
Other problems with prior art hand trucks, useful for carrying such unwieldy objects, is that their size and weight is such that it is difficult for one man to move them from one building or location to another in an automobile, or light utility vehicle, and their size is such that they occupy a substantial amount of space when not in use.
Yet another problem of the prior art hand trucks used to move unwieldy objects is that the prior art hand trucks are limited in the types of objects to be moved, being restricted primarily to objects having a lower surface that would fit on the planar upper surfaces of the lift platforms and which also had substantially vertical sides to engage the frame or lift plate of such trucks to prevent the lift trucks from being twisted out of the proper position for supporting the load.